Digi International Inc XBEEPRO2 Manual Do Utilizador

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XBee®/XBee‐PRO® ZB RF Modules 
© 2011 Digi International, Inc.
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In the figure above, t1, t2, and t3 represent the following events:
•T1 - Time when the module wakes from cyclic sleep
•T2 - Time when the module returns to sleep
•T3 - Later time when the module wakes from cyclic sleep.
The wake time and sleep time are configurable with software commands as described in the sections below.
Wake Time (Until Sleep)
In cyclic sleep mode (SM=4 or 5), if serial or RF data is received, the module will start a sleep timer (time 
until sleep). Any data received serially or over the RF link will restart the timer. The sleep timer value is 
settable with the ST command. While the module is awake, it will send poll request transmissions every 
100ms to check its parent for buffered data messages. The module returns to sleep when the sleep timer 
expires, or if the SI command is sent to it. The following image shows this behavior.